/Engine/Plugins/MovieScene/MovieRenderPipeline/Source/MovieRenderPipelineCore/Public/Graph/Nodes/MovieGraphFileOutputNode.h
This is called by the Game Thread containing the final output data for a given output frame. InRawFrameData contains a list of all of the data generated for this output frame, and InMask specifies which render layers within InRawFrameData should actually be written to disk by this output node.
void OnReceiveImageData ( [UMovieGraphPipeline](API\Plugins\MovieRenderPipelineCore\Graph\UMovieGraphPipeline) * InPipeline, [UE::MovieGraph::FMovieGraphOutputMergerFrame](API\Plugins\MovieRenderPipelineCore\Graph\FMovieGraphOutputMergerFrame) * InRawFrameData, const [TSet](API\Runtime\Core\Containers\TSet)< [FMovieGraphRenderDataIdentifier](API\Plugins\MovieRenderPipelineCore\Graph\FMovieGraphRenderDataIdentifier) > & InMask )